It looks like the next device from Chinese ereader maker Boyue has leaked on Youtube.
The Likebook Mars has a 7.8", 300 ppi Carta E-ink screen with frontlight and capacitive touchscreen. According to the description on Youtube, it runs Likebook OS on an octa-core Rockchip CPU with 2GB RAM and 16GB storage.
Edit: Boyue told me that Likebook OS is based on Android 6.0.1.
Weighing in at 290 grams, the Likebook Mars has a 2.8Ah battery and measures a mere 9.3mm thin. It also has Wifi, BT, a microSD card slot, and a headphone jack.
All in all this is almost the same ereader as the Likebook Plus, but there are a couple subtle improvements. The description says the Likebook Mars has twice the RAM, and a color-changing frontlight similar to what you can find on Kobo's ereaders.
That second detail was confirmed by another Youtube video:
There's no word yet on when the Likebook mars will be released.